The transformation equations are applied to the F-G type main-sequence stars [1]} which are provided with accurate photometric data. The sample of stars in the cited study reduced from 168 to 70 due to the absence of \(FUV\)  and \(NUV\)  magnitudes in GALEX DR7 [2]} database. We used the corresponding coefficients in Table 4 and Table 5, and estimated the \((U-V)_0\)  colours of 70 stars in question. Residuals (Fig. 11) and the statistical results (Table 6) show that combination of the luminosity class and metallicity provides more accurate \((U-V)_0\)  colours relative to the ones estimated by considering only the luminosity class. We should emphasize that the results corresponding only to the luminosity class are also consistent.
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